03/02/2026
💡 Today we present you a fundamental and incredibly impactful procedure: the percutaneous nephrostomy ( ). This seemingly simple intervention can be an absolute game-changer for patients facing urinary obstruction, and mastering it is a crucial step in your IR journey.
What is a PCN? 🤔
In a nutshell, a PCN involves placing a catheter directly into the renal collecting system to drain obstructed urine.
Common causes include kidney stones, tumors (intrinsic or extrinsic compression), strictures, or even post-surgical complications.
💉 Treatment:
• Patient positioning & pre-procedure imaging: We typically position the patient prone or oblique. Initial ultrasound (US) guidance helps us assess the degree of hydronephrosis and plan our access route.
• Access planning & anesthesia: Under US guidance, we identify a dilated calyx, preferably lower group of calyces to minimize vascular damage. Local anesthetic is infiltrated widely from the skin to the renal capsule. Good local anesthesia is key for patient comfort!
• Initial puncture: Using real-time ultrasound guidance, a small-gauge needle (e.g., 18 or 20 gauge) is advanced into the chosen calyx. You'll often see reflux of urine into the syringe when you're in the collecting system. This is a satisfying moment!
• Wire access: Once safely in the collecting system, confirming with a small amount of contrast, a guidewire (often a stiff, angled guidewire) is advanced through the needle. Under fluoroscopy guidance the wire placed in the renal pelvis and in the ureter when possible.
• Tract dilation: Over the guidewire, a series of dilators are used to create a tract from the skin to the renal pelvis, large enough for your chosen catheter. This is often done sequentially, starting small and gradually increasing the size.
• Catheter placement: A nephrostomy catheter (usually 8-14 Fr pigtail catheter) is advanced over the guidewire into the renal pelvis. The pigtail allows it to coil and stay securely in place. Once the catheter is in position, the wire is removed, and the pigtail forms.
• Confirmation & securement: We aspirate urine to confirm drainage and often inject contrast to confirm optimal position and exclude extravasation. The catheter is then securely sutured to the skin and connected to a drainage bag.
Percutaneous nephrostomy is more than just placing a tube; it is providing immediate relief, preventing sepsis, and preserving kidney function. It is a procedure that truly highlights the impact of interventional radiology. Get comfortable with it, practice your skills, and you will be saving lives!
